Honda bf8a block replacement

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mob
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Honda bf8a block replacement

Post by mob » Nov 19th, '17, 14:23

Earlier this year I posted about my Honda bf8a getting a hole in the block and also posted about my decision to buy a new outboard.  Well that never happened.  My prerequisites were twin cylinder, fourstroke with good reverse that would fit in my well (transom mount).  In fact I was looking for my bf8a, so have decided to try and save it.  
I have purchased a used block on ebay and, assuming it's ok, hope to get it going over the  Christmas break. The list of spares for this project so far is as follows :  head gasket,  manifold gaskets, thermostat housing gasket, thermostat (the old one fell to bits and was removed years ago), rings, oil pan gasket.....anything else?

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Tinggu
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Re: Honda bf8a block replacement

Post by Tinggu » Nov 19th, '17, 15:32

We have an elderly BF8. Do you know the reason for the hole? Anode failure? I would be interested in hoping to stop ours going the same way. Good luck with the project. Hope you'll keep us posted on the way.
Pete
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mob
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Re: Honda bf8a block replacement

Post by mob » Nov 19th, '17, 17:52

I guess it may have been anode failure, there was plenty of it still there but it was17 years old. A part of the jacket had cracked and blown off. I'm yet to dismantle it - the replacement is coming from Canada one day - because I don't want to forget what goes where, but when I do I'll let you know what's what. Hopefully I can get many more years out of it, like my car.

Ukuri
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Re: Honda bf8a block replacement

Post by Ukuri » Nov 19th, '17, 19:42

Good source for parts as well as accurate information and part numbers.
Good prices (compared to the outrageous prices charged by local dealers) and reliable and timely delivery. I can recommend them
http://www.boats.net/parts/search/Honda ... parts.html

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bachus
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Re: Honda bf8a block replacement

Post by bachus » Nov 19th, '17, 20:13

mob wrote:I guess it may have been anode failure, there was plenty of it still there but it was17 years old. A part of the jacket had cracked and blown off. I'm yet to dismantle it - the replacement is coming from Canada one day - because I don't want to forget what goes where, but when I do I'll let you know what's what. Hopefully I can get many more years out of it, like my car.

Based on the anode on my 1994 vintage Mercury, the anode can get honeycombed and I suspect at this point is at the end of it's life.
Jim
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MoodyBlue
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Re: Honda bf8a block replacement

Post by MoodyBlue » Nov 19th, '17, 20:27

Honda's have a thin section in the casting between the cylinder and water jacket. The rust/corrosion builds up in this area and blows a section usually approx 75 mm square.
The cure is to remove the head and clean out the water jacket, using long suitable diameter drill bits.
It is a problem I often encounter with my Seagull cast iron blocks.

As to your replace ment block, just meticulous clean, and a light hone of the bores.
"There is no perfect boat. There are only those shaded to your preferences.":-)

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mob
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Re: Honda bf8a block replacement

Post by mob » Nov 24th, '17, 09:50

My replacement block has finally arrived from Canada, hooray! I have not had the opportunity to open it and am unlikely to for a few days yet, boo!

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Re: Honda bf8a block replacement

Post by sailboatmike » Nov 24th, '17, 10:39

What you got a package and haven't opened it??????

Around here a package arrives and its like seagulls attacking chips, none of this, "Im a bit busy" routine.

You have far more self control than I ever would :lol:
Cheers Mike
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mob
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Re: Honda bf8a block replacement

Post by mob » Nov 25th, '17, 06:29

Whilst the packaging remains untouched it can stay inside on the table. As soon as it's opened it will be relegated to the shed, but it's 2 months since the last clean up so horizontal space is a mere memory.

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